Many devices have been disclosed and commercially employed over the years which cool or heat products by passing the product to be cooled or heated into an entrance opening of a device, conveying the product through the interior of the device where it is exposed to a cold or hot atmosphere, depending on the object to be achieved, and recovering the cooled or heated product from an exit of the apparatus. In some embodiments, the interior atmosphere is established by mechanical units which chill or heat the ambient air within the unit. In other embodiments, jets of cooled or heated air or vapor are directed at the product to be cooled or heated, in the attempt to increase the rate of heat transfer from or to the product, thereby reducing the amount of time that is required to achieve the desired degree of cooling or heating of the product.
The literature includes examples of apparatus in which the heat transfer medium, such as cryogen vapor or heated air, is impinged upon the surface of the product being cooled or heated. Recent examples of such literature include U.S. Pat. No. 6,263,680 and U.S. Pat. No. 6,434,950. However, examples such as these still suffer from a lack of efficiency in the heat transfer that can be attained in the course of carrying out cooling or heating by impingement of heat transfer medium.
Thus, there remains a need in this field for improved apparatus and methods for cooling and heating articles employing impingement techniques.